Carnosine as a Protective Factor in Diabetic Nephropathy

• Published in: Diabetes (New York, N.Y.) Vol. 54; no. 8; pp. 2320 - 2327
• Main Authors: Janssen, Bart, Hohenadel, Daniela, Brinkkoetter, Paul, Peters, Verena, Rind, Nina, Fischer, Christine, Rychlik, Ivan, Cerna, Marie, Romzova, Marianna, de Heer, Emile, Baelde, Hans, Bakker, Stephan J.L., Zirie, Mahmoud, Rondeau, Eric, Mathieson, Peter, Saleem, Moin A., Meyer, Jochen, Köppel, Hannes, Sauerhoefer, Sibylle, Bartram, Claus R., Nawroth, Peter, Hammes, Hans-Peter, Yard, Benito A., Zschocke, Johannes, van der Woude, Fokko J.
• Format: Journal Article
• Language: English
• Published: American Diabetes Association 01.08.2005
• ISSN: 0012-1797; 1939-327X
• DOI: 10.2337/diabetes.54.8.2320

Carnosine as a Protective Factor in Diabetic Nephropathy Association With a Leucine Repeat of the Carnosinase Gene CNDP1 Bart Janssen 1 , Daniela Hohenadel 2 , Paul Brinkkoetter 2 , Verena Peters 3 , Nina Rind 1 , Christine Fischer 1 , Ivan Rychlik 4 , Marie Cerna 4 , Marianna Romzova 4 , Emile de Heer 5 , Hans Baelde 5 , Stephan J.L. Bakker 6 , Mahmoud Zirie 7 , Eric Rondeau 8 , Peter Mathieson 9 , Moin A. Saleem 9 , Jochen Meyer 1 , Hannes Köppel 2 , Sibylle Sauerhoefer 2 , Claus R. Bartram 1 , Peter Nawroth 10 , Hans-Peter Hammes 2 , Benito A. Yard 2 , Johannes Zschocke 1 and Fokko J. van der Woude 2 1 Institute of Human Genetics Heidelberg, Heidelberg, Germany 2 Department of Nephrology, Endocrinology and Rheumatology, Fifth Medical Clinic, Mannheim, Germany 3 First Department of Pediatrics, University Hospital Heidelberg, Heidelberg, Germany 4 Second Department of Medicine and Departement of Cell and Molecular Biology, Third Faculty of Medicine, Charles University, Prague, Czech Republic 5 Department of Pathology, Leiden University Medical Centre, Leiden, the Netherlands 6 Department of Internal Medicine, University Medical Centre Groningen, Groningen, the Netherlands 7 Hamad Medical Corporation, Doha, Qatar 8 Service de Nephrologie A, Hopital Tenon, Institut National de la Santé et de la Recherche Medicalé, Paris, France 9 Academic Renal Unit, Southmead Hospital, Bristol, U.K 10 Department of Endocrinology and Nephrology, Third Medical Clinic, Heidelberg, Germany Address correspondence and reprint requests to Prof. Dr. Fokko J. van der Woude, Fifth Medical University Clinic Klinikum Mannheim, Theodor-Kutzer-Ufer 1-3 D-68135, Germany. E-mail: fokko.van-der-woude{at}med5.ma.uni-heidelberg.de Abstract The risk of diabetic nephropathy is partially genetically determined. Diabetic nephropathy is linked to a gene locus on chromosome 18q22.3-q23. We aimed to identify the causative gene on chromosome 18 and to study the mechanism by which the product of this gene could be involved in the development of diabetic nephropathy. DNA polymorphisms were determined in 135 case (diabetic nephropathy) and 107 control (diabetes without nephropathy) subjects. The effect of carnosine on the production of extracellular matrix components and transforming growth factor-β (TGF-β) after exposure to 5 and 25 mmol/l d -glucose was studied in cultured human podocytes and mesangial cells, respectively. A trinucleotide repeat in exon 2 of the CNDP1 gene, coding for a leucine repeat in the leader peptide of the carnosinase-1 precursor, was associated with nephropathy. The shortest allelic form ( CNDP1 Mannheim ) was more common in the absence of nephropathy ( P = 0.0028, odds ratio 2.56 [95% CI 1.36–4.84]) and was associated with lower serum carnosinase levels. Carnosine inhibited the increased production of fibronectin and collagen type VI in podocytes and the increased production of TGF-β in mesangial cells induced by 25 mmol/l glucose. Diabetic patients with the CNDP1 Mannheim variant are less susceptible for nephropathy. Carnosine protects against the adverse effects of high glucose levels on renal cells. AGE, advanced glycation end product ROS, radical oxygen species TGF-β, transforming growth factor-β Footnotes B.J., D.H., and P.B. contributed equally to this study. Accepted May 9, 2005. Received March 22, 2005. DIABETES